Technical Abstract:
Germplasm conservation of pineapple is crucial to secure the genetic variability of the genus for breeding programs and supporting new research. Long-term conservation is done through cryopreservation, by storing cells or tissues at ultra-low temperature in liquid nitrogen (LN; -196°C) or in the LN vapor phase (-150°C). Droplet-vitrification, a combination of droplet-freezing and solution-based vitrification were used to establish a protocol for cryopreservation of pineapple genetic resources. Excised shoot tips (1 mm) with one primordial leaf from three different accessions (Perola, an ornamental hybrid and MD2) of pineapple were pre-cultured for 48 h on solid MS medium containing 0.3 M sucrose. Three exposure times of PVS2 (30, 45 and 60 min.) were tested. The results showed a high survival rates to all three genotypes. The best time of PVS2 exposure varied among the genotypes and the highest number of shoots surviving the LN exposure was observed for the MD2 shoots exposed to PVS2 for 45 min (60%). Plants regenerated from LN stored shoots showed a typical growth for pineapple cultured in vitro and no morphological changes were observed.